Massive 4,800 MWh Battery Planned by Ex-Macquarie Bankers to Back Australia's New Energy Projects

A group of former Macquarie bankers has launched an ambitious venture to build one of Australia's largest battery storage systems. The project, featuring a six-hour duration and 4,800 MWh capacity, aims to support a wave of new renewable generation. Here’s everything you need to know.

Who is behind this massive battery project?

The company behind this initiative was established by former bankers from Macquarie Group, a global financial services firm known for its deep involvement in energy and infrastructure. These individuals leveraged their extensive experience in project finance and energy markets to create a venture that targets large-scale battery storage opportunities. The project is their first major undertaking, signaling a strategic shift toward backing renewable energy infrastructure. Their background gives the project credibility and access to capital markets, which are crucial for funding such a sizable asset. By drawing on their expertise, they aim to navigate the complexities of grid interconnection, regulatory approvals, and long-term offtake agreements.

What are the battery's capacity and duration?

The planned battery system boasts a storage capacity of 4,800 megawatt-hours (MWh) and is designed to discharge power over six hours. This makes it one of the largest batteries in Australia by energy capacity. The six-hour duration sets it apart from many existing big batteries, which typically have one- or two-hour durations. Such a setup allows the battery to store excess solar and wind energy during the day and release it gradually during the evening peak or when generation is low. The combination of high capacity and extended duration positions it as a grid-scale asset capable of providing multi-hour resilience, shifting renewable energy supply to match demand patterns more effectively.

Why is a six-hour battery important for Australia's energy grid?

A six-hour battery is crucial because it can address the evening peak demand period that often follows the drop in solar generation. Many short-duration batteries (1–2 hours) can only provide fast frequency response or short bursts of power, but they cannot sustain output through the entire peak window. With six hours of storage, this battery can deliver consistent power from late afternoon through the night, helping to replace coal and gas-fired generation. It also enhances grid stability by smoothing out the variability of renewables and reducing the need for costly backup fossil fuel plants. As Australia transitions to higher shares of wind and solar, longer-duration storage like this becomes essential for maintaining reliability without carbon emissions.

How will this battery support new generation projects?

The battery is specifically designed to underpin a swathe of new renewable generation projects. By providing a reliable storage outlet, it reduces the risk for developers of wind and solar farms who otherwise might face curtailment or low prices when supply exceeds demand. The battery can purchase electricity at low times and sell it during high-demand periods, creating a stable revenue stream that makes new projects more bankable. Furthermore, the battery can offer network services like frequency control and voltage support, which are increasingly valuable as more inverter-based generation connects to the grid. In essence, it acts as a giant sponge, soaking up surplus clean energy and releasing it when needed, thereby accelerating the deployment of additional renewable capacity.

What makes this project one of Australia's biggest?

With a storage capacity of 4,800 MWh, this battery will be among the largest ever built in Australia and globally. For comparison, the Hornsdale Power Reserve in South Australia (one of the first big batteries) started with 129 MWh. Even recent mega-projects like the Waratah Super Battery in New South Wales have around 1,680 MWh. This project’s size – roughly three times larger than many current records – reflects the growing need for bulk energy storage to support deep decarbonisation. The six-hour duration also signals a shift from fast-response batteries to those capable of longer discharge, aligning with the requirements of a grid approaching 100% renewables. The involvement of former Macquarie bankers underscores the financial sector’s confidence in battery storage as a scalable, investable asset.